Op Tech Flashcards
Cavo-surface margin angle
- the angle at the junction between the prepared and unprepared surfaces
- should be between 60-120 degrees, 90 ideally
cavity margins
the junction between the walls of the cavity and the unprepared tooth surface
line angles
the line formed at the junction between two surfaces within the cavity
point angles
the angle formed between three prepared surfaces in the cavity
occlusal floor
the surface at the bottom of the cavity, parallel to the occlusal plane, that lies over the pulp
gingival floor
the surface at the bottom of the cavity, parallel to the occlusal plane, bound by the gingival margin
axial wall
a vertical wall within the cavity that is parallel to the long axis of the tooth
pulpal axial wall
axial wall that surrounds the pulpal tissue
buccal / lingual axial wall
axial wall that forms the border of the cavity, bounded by the Cavo-surface margin
flat plastic
manipulation of shapeable materials ie composite or glass ionomer
matrix band
used to rebuild margin walls
excavator
removal of caries or thinned enamel, removal of materials
tweezers
handling small objects ie wedges
mirror
viewing intraorally, tissue retraction
Describe the dentine bonding process.
- acid etch applied (35% phosphoric acid), opens tubules by removing smear layer, leaving collagen network, increased wettability
- prime and bond applied, primers hydrophilic end binds to the hydrophilic dentine tubules, the hydrophobic methacrylate binds to the hydrophobic adhesive
What is in prime and bond?
HEMA
resin bis-GMA
camphorquinone
acetone
What are the principles of caries removal?
- Identify and removal carious enamel.
- Remove enamel to identify the extent of caries and the ADJ.
- Progressively remove caries in dentine, from ADJ and circumferentially deeper.
- Remove deep caries over the pulp.
- Modify cavity design, smooth edges, prepare for chosen filling material (ie retentive form = amalgam).
- Smoothing of internal line and point angles.
- Smoothing of the Cavo-surafce margins.
What are the components of a dental handpiece?
- head (bearings, rotor, chuck, bur, backcap)
- neck
- body
- coupler
What are the safe for use checks?
- check the backcap doesn’t rotate anticlockwise
- apply tension to bur to ensure it doesn’t come loose
- apply tension to the coupling to ensure it doesn’t come loose